Syncope/Dizziness Specialist


Cardiologists located in Jacksonville, FL

Syncope, or fainting, is a momentary loss of consciousness that happens most often when blood pressure is so low that the heart can’t pump enough oxygen-rich blood to the brain. Although syncope can be a one-time problem triggered by a benign cause, it can also be a symptom of an underlying heart condition. Board-certified cardiologist Ramon Castello MD, FACC, FASE of CardioHealth in Jacksonville, Florida, has the experience and expertise to diagnose unexplained fainting episodes and treat underlying cardiovascular causes. To learn more, call or book an appointment online today.

Syncope/Dizziness Q & A


What is syncope?

Commonly referred to as fainting or passing out, syncope is the temporary loss of consciousness brought on by insufficient blood flow to the brain.

When you’re about to faint, you may feel dizzy, lightheaded, or nauseous. Your skin may also feel cold and clammy. Just before you lose all muscle control and pass out, your field of vision may go wholly white or completely black.

After fainting, you may be unconscious for a minute or two before you wake back up. It’s important to rest for 15-30 minutes after fainting, as standing up too soon can lead to another fainting spell.

What is vasovagal syncope?

Vasovagal syncope (VVS), also known as neurocardiogenic syncope or reflex syncope, is the most common type of fainting.

VVS occurs when the area of your autonomic nervous system that controls blood pressure and heart rate stops working as it should, usually in response to an outside trigger. Common triggers include:

  • Heat exposure
  • Dehydration
  • Standing for too long
  • Emotional stress
  • Seeing blood or having blood drawn
  • Drop in blood sugar

VVS is usually a benign condition that you can avoid once you know your triggers. Because you can’t always avoid your known triggers, however, it’s important to lie or sit down if you feel a fainting episode coming on.

What is cardiac syncope?

When fainting spells happen regularly, or when they can’t be definitively linked to a trigger like dehydration, overheating, or a sudden positional change, they may be a symptom of a serious heart or vascular condition.

Unlike VVS, cardiac syncope usually occurs suddenly. It can also occur without the dizziness, nausea, clammy skin, and other pre-syncope symptoms that usually happen with VVS.

Common causes of cardiac syncope include:

Heart arrhythmias

Heart arrhythmias, or abnormal heart rhythms, can make it harder for your heart to pump oxygen-rich blood to your brain efficiently.

Several types of cardiac arrhythmias can cause syncope, including bradyarrhythmias, which occur when your heart beats too slowly, and tachyarrhythmias, which occur when your heart beats too quickly.

Aortic valve stenosis

Your aorta is the large artery that carries oxygen-rich blood from your heart to the rest of your body. When the valve between your heart and your aorta (aortic valve) becomes severely narrow, it can reduce the amount of oxygen that reaches your brain.  

Why is it important to diagnose unexplained syncope?

Losing consciousness is always a scary experience. It can compromise your life or that of others, depending on what you are doing (climbing a ladder, driving). Therefore, it’s vital for anyone who has experienced syncope to undergo a comprehensive cardiovascular evaluation.

Besides considering your medical history and assessing your blood pressure, heart rate, and overall condition, Dr. Castello may have you undergo an electrocardiogram (ECG), an echocardiogram, or a stress echocardiogram to get more information about your heart.

A test called ANSAR is specifically designed to evaluate the autonomic nervous system. Many patients are referred to CardioHealth to undergo this test. Dr. Castello and his team have experience with thousands of ANSAR tests and results.

Often, patients with dizziness and syncope are referred to a neurologist for evaluation. Then the cardiologist and neurologist have to work together to investigate the causes and best treatment for the syncopal or near-syncopal episode.

Dr. Castello (cardiologist) and Dr. Asad (neurologist) have partnered in the creation of the “Syncope clinic.” The clinic aims to provide the most comprehensive and seamless neuro-cardiac evaluation of these patients. Dr. Asad’s office is conveniently located within 500 feet of CardioHealth.

Treating the underlying cause of cardiac syncope is the best way to stop the problem. To learn more, call or book an appointment online today.

Conditions Treated